P0403: Exhaust gas recirculation control circuit

What the code tells you on its own

System
Powertrain

Engine, fuel, air, ignition, emissions and transmission. The overwhelming majority of what workshops bring to the AI.

Functional group
EGR
Subsystem
Auxiliary emission controls

Diagnostics

What we see when P0403 turns up

Measured across the diagnostics run through Wrenchlane, not taken from a reference table. Figures as of 2026-10-06.

Diagnostics
9

April 2026 to September 2026

Separate workshops
4

Not one shop meeting it repeatedly

Arrived code only
11%

No symptom description entered at all

Most common marque
Skoda

Where we have seen it most

These are counts from our own work, not a claim about how common the fault is across all vehicles. They describe what independent workshops brought to us, which is a narrower and more specific thing.

Real cases

Real cases with P0403

Diagnoses of P0403 on real cars, written up: the car, the codes it came in with, the causes ranked and what to check first.

P0403

What P0403 usually turns up with

Measured across our own diagnostics. The multiplier is how much more often the two appear together than chance would predict, so a high number means the pair is telling you something a single code is not. Codes rarely arrive alone, and reading the set is usually faster than chasing the first one on the list.

Code What it is Seen together Versus chance
P1258 Manufacturer-specific, meaning depends on the marque 3 times 213.4x
P1690 Manufacturer-specific, meaning depends on the marque 3 times 213.4x
P1925 Manufacturer-specific, meaning depends on the marque 3 times 213.4x
P1937 Manufacturer-specific, meaning depends on the marque 3 times 213.4x
P3100 Manufacturer-specific, meaning depends on the marque 3 times 213.4x
P0243 Turbocharger wastegate solenoid A 3 times 160.1x

FAQ

Frequently asked questions

How do I run a diagnosis?

Select the vehicle on Start, click the Diagnostic card and choose New diagnostic. Fill in the description, the error codes and the mileage, then click Analyze.

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Do I have to type the codes from my scan tool?

No. Click the camera button next to Error codes and take or choose a photo of the scan tool's screen; WrenchLane reads the codes and their descriptions into the form. You can also speak them with the microphone.

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Are the public fault code pages built from my diagnostics?

They use diagnostics run in WrenchLane, with no workshop, customer, registration number or VIN shown. Each fault code page shows how often the code was seen and in how many workshops.

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Run P0403 against the car in front of you

Enter the code and the symptoms and get ranked probable causes for that specific vehicle, with the checks in the order worth doing them. Free account, no card.